A. Field of the Invention
The present invention is related to transceivers in communication systems. In particular, the present invention relates to an apparatus and method for selecting a supported signal path for a transceiver in a communication system.
B. Description of the Related Art
Most modem telephone customer locations typically have four wires coming into the customer premise location from the central office of a telephone company.
FIG. 1 is a block diagram showing an exemplary signal path configuration between a central office and a customer premise location, such as a person""s home. The customer premises boundary 102 is the demarcation point between a loop 104 to a central office, and a customer premise location 106. The loop 104 typically consists of at least one pair of wires to facilitate data transmission, such as an analog telephone communication. Other services such as ISDN (Integrated Services Digital Network), or high speed network access, may also be provided.
Two pairs are shown in FIG. 1: a first pair 108, 110 is providing high speed service, and a second pair 112, 114 is providing low speed service. The two pairs 108, 110 and 112, 114 are connected to the customer premise location 106, where they may be used to distribute communication services throughout the customer premise location 106.
In FIG. 1, only one distribution path is shown and is terminated at an RJ-11 jack 116. The high speed service pair 108, 110 is shown as being connected to the outer pair 118, 120 in the customer premise location 106. The low speed service pair 112, 114 is shown as being connected to the inner pair 122, 124 at the customer premise location 106. The outer pair tip wire 118 is shown as connected to the second pin 126 of the RJ-11 jack 116, and the outer pair ring wire 120 is shown as connected to the fifth pin 128 of the RJ-11 jack 116. The inner pair tip wire 122 is shown as connected to the third pin 130 of the RJ-11 jack 116, and the inner pair ring wire 124 is shown as connected to the fourth pin 132 of the RJ-11 jack 116. The inner pair of wires 122, 124 located on the third and fourth pins 130, 132 in the RJ-11 jack 116 are usually used for low speed services, such as standard telephone service. The outer pair 118, 120 located on the second and fifth pins 126, 128 of the RJ-11 jack 116 have typically been used for higher speed services, such as ISDN. The first and sixth pairs 134, 136 of the RJ-11 jack 116 are not used. Some communication systems may utilize the first and sixth pins 134, 136, such as if a third pair is used to provide additional or supplemental communication services. Other distribution systems and other types of jacks are often commonly used. In the present invention, it may be implemented in many of these configurations as well.
Although the configuration shown in FIG. 1 has been the standard and desired implementation, in reality there has been much variation due to, for example, to installer error (or inconsistency) and customer modification to equipment.
As a result, it has been difficult to design equipment that relies on a standard mapping of services to pin configurations.
Needed is an apparatus and method that is able to sense the configuration of customer premises"" wiring, and that can, accordingly, adapt to the sensed configuration, enabling a device, such as a transceiver, to utilize the proper wires for the services being offered.
Also needed is a digital subscriber line transceiver that is able to automatically determine the type of DSL service being provided and the signal path over which the service is being provided.